Arsene Wenger says it was an easy decision to start Alexandre Lacazette over Danny Welbeck in Arsenal's Europa League quarter final.

Lacazette was named in the Gunners starting line-up for the first time since the start of the year after losing his place to January signing Pierre-Emerick Aubameyang and undergoing a knee operation.

On his return from injury at the weekend, the French international came off the bench and scored from the penalty spot in a 3-0 win over Stoke.

Playing from the start on Thursday night, Lacazette justified his selection with a brace of goals to help Arsenal beat CSKA Moscow 4-1 in the first leg at the Emirates Stadium. Aaron Ramsey also scored twice as the Gunners ran riot with four goals in the first half.

Speaking to BT Sport prior to the game, Wenger admitted playing Lacazette was a risk, but one he had to take.

"It is a little bit [of a risk]. Will he last the whole game? Certainly not," he said.

"Danny Welbeck had a back problem so the decision was quite easy. Let’s hope he will last the whole game.”